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It is easy to do to increase speed. It is .2 the recommended SP for cooling, but can very alittle just will get noisier.
Re configure go into install and set up Zones or duct assessment. You can limit flow to low medium or max with no limits. in which will reduce blower RPM. Their is alot this stat does and After 3 years Im still learning. I install lots of these controllers every year.
Every 24 or 48 hours furnace does a duct assessment for damper limits. I think I am sure on this but might be wrong.

Interestingly, I just did a test and set only the smallest zone (basement) to call for cooling. With this test, I found that the system opens the dampers (at least partially) for both of the other zones and ran at a lower CFM overall. The static was .44.

With only the basement zone calling, it ran at 1375 CFM (instead of the usual 1750 as when other zones run) -- the basement was at 525 CFM, and the other zones were a little over 400 CFM each (with the dampers for the other zones fluctuating between 3 and 7 -- 15 is fully open).

So how does it know to run at lower CFM -- I don't see that set anywhere? Is that just something the system knows to do via its computer and due to the duct assessment? Why do the other dampers open when only the basement is calling? When the main zone or bedroom zone is running by itself, it does not crack the other dampers.

As far as airflow limits setting, I definitely don't want to set the basement zone to max -- as its too loud in the basement theater room then. In fact, I have it set at "low". Does the low setting cause the dampers to open for the other zones, when only the basement is calling? Or is that just due to the small size of the basement zone? At most I'll set it to medium airflow -- I can not set it to "high" or "max" -- way too noisy.

It is easy to do to increase speed. It is .2 the recommended SP for cooling, but can very alittle just will get noisier.
Re configure go into install and set up Zones or duct assessment. You can limit flow to low medium or max with no limits. in which will reduce blower RPM. Their is alot this stat does and After 3 years Im still learning. I install lots of these controllers every year.
Every 24 or 48 hours furnace does a duct assessment for damper limits. I think I am sure on this but might be wrong.

It does the duct assessment every 24 hours -- at 1:00 PM.

I set the airflow to "low" for the basement -- as I want the theater room quiet. Main floor is max and bedrooms are on "high" (the default).

Where do you get that 0.2 IWC static pressure is correct for cooling?
Why does he need to do this? He's not getting any static shutdown messages nor is he complaining of noise at the registers.
And you have a lot to learn. It's daily at a default of 1:00 p.m. The newer controller will allow you to change the time of day this occurs.

I don't know why you post on these Infinity threads. The vast majority of the time you do nothing but confuse the poor homeowner.

I knew not to listen to him when I saw the 24/48 hours. I've known since I bought my house that it runs every 24 hours at 1:00 PM (and can't be changed on my version of the Infinity stat).

Interestingly, I just did a test and set only the smallest zone (basement) to call for cooling. With this test, I found that the system opens the dampers (at least partially) for both of the other zones and ran at a lower CFM overall. The static was .44.

With only the basement zone calling, it ran at 1375 CFM (instead of the usual 1750 as when other zones run) -- the basement was at 525 CFM, and the other zones were a little over 400 CFM each (with the dampers for the other zones fluctuating between 3 and 7 -- 15 is fully open).

So how does it know to run at lower CFM -- I don't see that set anywhere? Is that just something the system knows to do via its computer and due to the duct assessment? Why do the other dampers open when only the basement is calling? When the main zone or bedroom zone is running by itself, it does not crack the other dampers.

CFM drops based upon demand and the amount of air it has calculated that zone can handle. It can actually go just a bit lower (approx. 70% of programmed CFM).

Although the other zones weren't 'calling', there was still some room for improvement. So, air was relieved to those zones. The system will over cool a space up to 3 degrees below setpoint to avoid equipment shutdown.

As far as airflow limits setting, I definitely don't want to set the basement zone to max -- as its too loud in the basement theater room then. In fact, I have it set at "low". Does the low setting cause the dampers to open for the other zones, when only the basement is calling? Or is that just due to the small size of the basement zone? At most I'll set it to medium airflow -- I can not set it to "high" or "max" -- way too noisy.

the 'low' setting is causing the other dampers to relieve more air. See minimum air flow requirements.

For noise reasons, I also don't want to put the bedroom zone at max.

What would be the benefit of setting all zones to max airflow limits?

Lower static pressures. You already know the down side - noise at the registers.

the 'low' setting is causing the other dampers to relieve more air. See minimum air flow requirements.

Thanks. I'll have to see what happens in the winter then. As the heat will likely be running more in the basement, than the other zones. At the "low" airflow setting in the basement, that might cause the other zones to get too hot -- since they'll be opened to relieve the air there.

The 400 CFM cooling in the non-calling zones didn't seem to drop the temperature there (it would probably need to run a real long time). The temps held steady. However, since the basement will likely have longer run times for heat, I could see it effecting the other zones. I'll have to experiment.

Well there is a lot of Pros here that don't sell the infinity system or even care to, so some of us pros have zero experience with a system like yours. If you would have hired a Pro to install yours we would not even be having this conversation,right? my question to you is why would you install a single stage comfort series a/c unit with that Infinity system? I know some builders will do that to get out cheap, so maybe it was like that when you bought the house, to me it's like buying a Corvette with a V6 but I really don't think that is a fair statement you made about knowing more about your system than the Pros, I guess if you have to work on something everyday you do have a tendency to know more about it that most folks.

__________________________________________________ _______________________“Experience is a hard teacher because she gives the test first, the lesson afterwards". -Vernon Law-

I Know the stat

I knew not to listen to him when I saw the 24/48 hours. I've known since I bought my house that it runs every 24 hours at 1:00 PM (and can't be changed on my version of the Infinity stat).

It always amazes me when I know more about my system than the pros.

I did say I was still learning and if you know so much why are you on here asking questions about Static pessures. I do know the Infinity controller pretty good but the exact time on duct assessment was not sure if it was every 24 or 48 hours shoot me. As far as going in and showing you how to do duct assessment manually that is all I was trying to do. As far as .2 SP I was just trying to give you numbers laid out in fan charts. Good Luck

I did say I was still learning and if you know so much why are you on here asking questions about Static pressures.

Yea I agree then you have the yada, yada, yada that checks in that don't help his cause at all just places another
"free" sales pitch, but in the real world who really cares? some just don't get it until it finally gets them.

__________________________________________________ _______________________“Experience is a hard teacher because she gives the test first, the lesson afterwards". -Vernon Law-

Well there is a lot of Pros here that don't sell the infinity system or even care to, so some of us pros have zero experience with a system like yours. If you would have hired a Pro to install yours we would not even be having this conversation,right? my question to you is why would you install a single stage comfort series a/c unit with that Infinity system? I know some builders will do that to get out cheap, so maybe it was like that when you bought the house, to me it's like buying a Corvette with a V6 but I really don't think that is a fair statement you made about knowing more about your system than the Pros, I guess if you have to work on something everyday you do have a tendency to know more about it that most folks.

The builder hired the company that installed my system. Two stage was not one of the options for the a/c unit -- I did the highest level upgrade for HVAC that was on the options sheet. But if I knew what I knew now -- I would have insisted on two stage a/c and had them price it out. According to Carrier's website, the company my builder used is a factory authorized Carrier dealer and at least one tech there has NATE certificiation.